Breathable-waterproof footwear

ABSTRACT

An article of footwear including an outer sole on which an outer upper is mounted, the upper including several pieces assembled together by stitching. The pieces of the upper are made of breathable-waterproof material, at least the visible assembly seams of the upper being covered by a waterproofing strip arranged on the outside of the upper. The upper includes a three-layered laminated material including a breathable-waterproof membrane, sandwiched between an inner lining fabric and an outer envelope fabric.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims priority under 35 U.S.C. §119 of French Patent Application No. 06.06705, filed on Jul. 21, 2006, the disclosure of which is hereby incorporated by reference thereto in its entirety.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The invention relates to the field of footwear, and more particularly to sports shoes, particularly for walking, running, that are breathable and waterproof.

2. Description of Background and Other Information

In the context of the invention, the term waterproof refers to a shoe which is waterproof or water-resistant, meaning a shoe in which at least one functional layer of the upper acts at least as a barrier to water or other liquid penetration. The term breathable-waterproof, in this context, means that the shoe allows water vapor to escape through the upper, i.e., from the foot out (perspiration), while being impervious to water coming in from the outside.

A shoe is conventionally made of an outer sole, which can be flexible or rigid, on which an upper is mounted that covers the user's foot.

The upper must form a three-dimensional envelope that is as close to the shape of a user's foot as possible. This upper is most of the time made of several pieces, which are cut out and assembled to one another by means of seams, so as to form the three-dimensional envelope. Generally, the shape of such pieces and their constituent materials are dependent upon the position of the pieces and their intended function. In the case of a sports shoe, the upper can also include attached protective and/or shaping elements such as a front end reinforcement, generally made of thick leather (or similar material) or rubber, and a heel stiffener.

In most shoes, and particular sports shoes, the upper includes inner and outer lateral quarters, which are separated by a longitudinal opening and are adapted to be moved closer to one another by means of a tightening mechanism, usually a lace mechanism arranged along each of the edges of the opening.

The typical construction of a so-called waterproof or breathable-waterproof shoe is disclosed in U.S. Pat. No. 4,599,810.

Such a shoe includes an outer upper made of breathable material, normally non-waterproof, such as leather or fabric, and an inner liner arranged inside the outer upper, made of breathable-waterproof material, generally including a breathable-waterproof membrane, such as sold under the trade names GoreTex®, Sympatex®, Event®, etc.

The liner is made of several pieces stitched together, each stitch being then covered by a sealing strip.

This construction is complicated and costly because it requires an additional layer (liner) to be made, because the breathable-waterproof material used for the liner is very expensive, and because all the stitches must be waterproofed. The material used for the liner is generally inextensible, which makes it even more complicated and expensive to manufacture.

In addition, the material used for making the liner and the sealing strip is relatively fragile, and it is important to not damage it in order to have a truly waterproof construction. For this reason, the liner is completely hidden inside the shoe.

In addition, the waterproof liner is in direct contact with the foot, which can be uncomfortable as the material is generally inextensible and causes a “dry touch” for the wearer, i.e., in contrast to a soft or cozy sensation, contrary to traditional shoes having foam liners that are softer or cozier to the touch.

Naturally, although comfort foams are generally provided, they are arranged between the waterproof liner and the outer upper, thus quite far from the foot. In addition, such comfort foams are not protected from moisture and can become wet by water penetrating through the non-waterproof outer-upper. If such foams become wet, the comfort of the shoe is naturally affected, even if the user's foot remains dry.

Finally, such waterproof liners do not typically extend up to the upper end of the shoe, which can also be detrimental, moisture and water penetrating inside the shoe through the upper, non-waterproof edge of the shoe.

It is also known to waterproof leather shoes by applying a sealant, such as oil, wax, rubber, or any other waterproof material, in the outer upper of shoe. The drawback of such waterproofing techniques is that they close the pores of the leather, and therefore eliminate any breathability, causing moisture from perspiration to condense around the foot. In addition, these waterproofing techniques do not allow the holes left by the stitching during assembly of the upper to be completely closed.

Finally, the coating, depending upon its type, must be reapplied more or less frequently.

There are also completely waterproof shoe constructions, such as rubber boots, made of waterproof material, molded and welded, but such boots do not allow any moisture to escape from inside the boot, therefore causing such boots to be uncomfortable and unpleasant to wear. In addition, such boots generally do not include any means for tightening and cannot be used in sports such as walking or running.

SUMMARY OF THE INVENTION

The present invention overcomes the aforementioned drawbacks.

The invention provides an improved waterproof construction for an article of footwear, such as a shoe, and, more particularly, a breathable-waterproof construction. The invention also optimizes the construction of the article of footwear.

The improved and optimized footwear according to the invention is of the type including an outer sole on which an outer upper is mounted, the upper including several inlays assembled by seams, the inlays of the upper being made of breathable-waterproof material, and at least the visible assembly seams of the upper being covered by a sealing strip arranged outside the upper.

With this construction, the boot is waterproofed from the outside and therefore has low or no risk of water penetration. In other words, the outer upper gets its primary function back, which is to constitute a waterproof barrier to outside elements, including water and moisture. In addition, optional comfort elements provided inside the waterproof outer upper do not risk becoming wet and damaged, which results in greater comfort for the wearer. Furthermore, the construction of the upper, with waterproofing from the outside, is much easier to carry out as it does not require an additional liner to be made.

Finally, arranging a sealing strip outside of the upper gives the boot assembly a very particular aesthetic appearance. Moreover, the strip protects the seams from abrasion.

BRIEF DESCRIPTION OF DRAWINGS

The invention will be better understood from the description that follows, with reference to the annexed schematic drawings showing several embodiments by way of non-limiting examples, in which:

FIG. 1 shows a top view of a shoe according to the invention;

FIG. 1 a is a view similar to FIG. 1 according to an alternative embodiment;

FIG. 2 is a cross-sectional, schematic view along the line II-II of the shoe of FIG. 1;

FIG. 3 is a cross-sectional view along the line III-III of the shoe of FIG. 1;

FIG. 4 is a view similar to FIG. 2 according to another embodiment of the invention;

FIG. 5 is a detailed view of the material of the upper;

FIG. 6 is a view similar to FIG. 4, in partial perspective, according to another embodiment of the invention.

DETAILED DESCRIPTION OF THE INVENTION

FIG. 1 shows a shoe, in this case a sports shoe 1, made of an outer upper 10, an outer sole 2, the upper 10 being capable of being mounted on the outer sole 2 by any known technique, for example by gluing, overmolding, or other technique. Although the term “shoe” is used in describing the illustrated embodiments of invention, the term is not intended to be limiting, i.e., the invention encompassing footwear in general, including that which include upper edges that lie beneath the ankle, those at the ankle, and those that extend above the ankle.

The upper 10 of the shoe is substantially a flexible upper, that is, formed of primary pieces of flexible material, or relatively flexible materials, while including complementary rigid or semi-rigid elements, particularly for shaping the shoe. Such complementary materials particularly include a heel stiffener 11, arranged inside the upper 10 and shown in broken lines in FIG. 1, and a front end piece 12, arranged at the front end of the upper 10 and used for shaping the upper 10 in the toe area as well as for protecting the upper. In the assembly shown, the end piece 12 is molded in TPU, PU, PVC, textile or rubber, glued directly on the upper before assembly on the sole 2.

Depending upon the embodiment and/or the type of shoe, such an end piece 12 can be provided inside the shoe, in the same manner as the heel stiffener, or can be omitted.

The assembly which comprises the upper 10, in the illustrated embodiment, includes a vamp 13 made of several parts 13 d, 13 c assembled by a seam 16 c, such as stitching, which cover the entire front and rear of the wearer's foot. The vamp 13 can also be made in one piece.

The upper also demarcates a horizontal opening 4 for insertion of the foot inside the shoe, and a tightening zone 5 in the area of the wearer's instep.

In the area of the instep, the vamp 13 or part of the vamp 13 d can be a unitary piece, i.e., a single piece, or, as shown in the illustrated embodiment, it can demarcate a longitudinal opening 14 inside of which a tongue 15 is positioned. In any case, the assembly of the vamp 13 and tongue 15 (and therefore the upper 10) is closed, and the tongue 15 can be connected to the vamp 13 by more flexible flaps of material forming gussets.

In the illustrated embodiment, the vamp 13 and the tongue 15 are made of breathable-waterproof material constituted of three laminated layers, namely, from outside-in (see FIG. 5):

-   -   a first layer 13 a made of extensible, polyester-,         polyamide-based repellent-treated material having a resistance         to abrasion of 30 cycles minimum, according to the DIN/ISO         05470-2 standard;     -   a second layer 13 b made of a breathable-waterproof membrane         such as a PU film, a membrane known by the trade names Gore®,         Sympatex®, Event®; and     -   a third layer 13 c made of a mesh of polyester or polyamide,         this layer 13 c being less extensible than the layer 13 a. This         third layer can be omitted in certain less stressed areas (for         example the heel comfort zone); it can also be associated with a         comfort foam including (or not including) 1 to 8 mm perforations         and laminated at the same time.

The three-layer assembly constitutes a slightly extensible complex having an elongation rate comprised between 30% and 150%, which enables the upper to properly adapt to the volume of the foot.

The extensibility should not be too substantial so as not to hinder the tightening of the shoe. Extensibility is however substantial, as it allows a pattern-cutting requiring a minimum of seams, and therefore a minimum of labor for waterproofing, while providing the upper with a very aesthetically pleasing appearance.

Good results can be achieved with a polyester-based complex in which the various layers have the following compositions:

-   -   first polyester layer;     -   second PU film layer (membrane);     -   third polyester “mono mesh” layer.

Even if the first layer 13 a does not have a very strong resistance to abrasion, for example 30 cycles, in accordance with DIN/ISO 05470-2 standard, its combination with the third layer 13 c, which is less extensible, surprisingly provides the assembly with resistance to abrasion on the order of 100 cycles, in accordance with the DIN/ISO 05470-2 standard on the Martindale machine, and is adequate for use in sports shoes.

Depending on the type of application of the shoe, different abrasion resistance values, more or less substantial, can be implemented.

The tongue 15 is made of the same material as the vamp 13 and is lined, as known, in its central area with foam cushioning or equivalent.

Because this material is very flexible and thin, the edges of the tongue 15 are sufficiently flexible to constitute gussets. The gussets can also be constituted of appropriate inlays made of an identical or different material.

As mentioned above, the assembly of the vamp 13 and tongue 15 can be made as a unitary piece.

In the illustrated embodiment, the tongue 15 is assembled to the upper by means of turned under seams 15 a that can be made impervious, as known, by sealing strips (not visible in the drawing) arranged therein. Such turned under seams 15 a are considered to be invisible, not apparent when the shoe is worn. Keepers 25 adapted to receive a tightening lace 26 are fixed by stitching and/or gluing on the vamp 13 along the edges of the opening 14. These keepers 25, constituted by folded straps, are fixed by stitching and/or gluing on the vamp 13, and the assembly is reinforced by means of a strip 30 made of waterproof material, such as PU/PVC or polyester, fixed by gluing. The method for fixing these keepers 25 can be such as disclosed in the commonly owned patent document FR 2 865 616 and U.S. Patent Application Publication No. 2005/0166426, the disclosure of the latter of which is hereby incorporated by reference thereto in its entirety.

FIG. 3 shows a cross section of the shoe in the heel area, that is, in a zone where comfort elements are arranged.

In this case, a lining 19 is fixed to the vamp 13 in the area of the vamp's upper end, by means of a turned-under seam 19 a. This seam 19 a, of the invisible type, is made waterproof in a known manner by a sealing strip 19 b arranged on the inside. The lining 19 extends to the area of the insole 3 and is assembled to the insole at the same time as the vamp 13 by a seam, such as stitching 3 a, locally or over the entire upper.

One comfort foam 20, or a plurality/several comfort foams 20, is/are sandwiched between the lining and the vamp 13 at appropriate locations, where comfort is desired.

Depending upon the type of shoe, the lining 19 can be provided over the entire surface of the vamp 13, or over part of it, or the liming can even be completely omitted. In such case, the turned-under seam 19 a is hidden, that is, invisible, and does not need to be protected by an outer sealing strip.

Furthermore, the turned-under seam is in a zone that is less exposed to moisture, and the inner sealing strip could, in some cases, even be omitted.

The upper 10 also includes, in its lower portion, a quasi-peripheral reinforcement 16, which extends from one end to the other end of the toe cap 12 by extending around the rear of the shoe.

This reinforcement 16 extends down to the bottom of the upper in the so-called lasting-allowance area.

In the embodiment of FIG. 2, the reinforcement 16 is fixed to the insole, referred to as the Strobel 3, at the same time as the upper 10 by means of a common seam/stitching 3 a.

The outer sole 2 is then fixed to the assembly by any known means, for example, by gluing.

Depending upon the type of shoe, the insole 3 could be more rigid than a Strobel sole, the upper being then assembled to the insole by gluing.

The reinforcement 16 is made of waterproof and abrasion-proof material, in any case more resistant than the material of the upper 10. It can be made, for example, of a laminated PU layer/non-woven layer such as PU/PVC, non-woven polyester.

The reinforcement 16 is fixed to the upper 10 by a seam 17. In the illustrated embodiment, the reinforcement 16 includes two lateral portions 16 a and a rear portion 16 b, assembled together by a visible seam 16 c after being superimposed. The seam 16 c also assembles the front 13 d and rear 13 e portions of the vamp 13.

According to the invention, each of the seams 16 c, 17 is covered by a sealing strip 18. In order to optimize the waterproofness, the reinforcements 16 could also be assembled to the vamp 13 by means of ultrasonic welding, or by means of other type of welding, or by means of gluing.

The sealing strip can be, for example, that which is sold under the trade name Capri de Framis® and constituted of a layer of polyurethane glue 18 a or any other thermofusible adhesive material, and of a textile layer 18 b made of abrasion-resistant and extensible material.

Depending upon the embodiment, the textile layer can include polyamide and spandex, while the strip 18 is made of 62.3% polyurethane, 27.3% polyamide, and 10.4% spandex.

Other materials can be selected for the strip, particularly as a function of the type or types of material of the upper.

The width of the strip is 12 mm, but can be between 5 mm and 20 mm. Such a strip 18 is waterproof and also very extensible. Its elongation rate is on the order of 200% in the illustrated embodiment, and could advantageously be between 30% and 300%.

The extensibility of the strip 18 enables the latter to deform and to easily adapt to the outline of the seams 16 c, 17, which are not completely rectilinear.

In addition, its width ensures that the strip indeed covers all of the seams, even if its direction slightly differs from that of the seams.

The sealing strip 18 offers numerous advantages:

-   -   first, it waterproofs the upper from the outside, which         guarantees against any risk of water penetration, for example,         through the seams or through the thickness of the material;     -   it protects the seams against abrasion;     -   it provides a very innovative and aesthetically attractive         appearance.

With respect to aesthetics, one can select a sealing strip having a color that contrasts with or is similar to that of the upper material.

Finally, the layer of thermofusible adhesive creeps and, thereby, becomes at least partially infused into the interstices between the fibers of the textile material of the upper and contributes to in-depth waterproofing.

The sealing strip 18 can also be used beyond the seams for an optimum aesthetic appearance. Thus, in the illustrated embodiment, the sealing strip forms a downwardly-open V in the heel area, only one branch of which covers the seam 16 c between the two reinforcement portions 16.

The pattern cutting of the vamp 13 and reinforcements 16 must also be designed so that the assembly seams are as flat as possible, and in any case, without any substantial change in the curvature so as not to hinder the positioning of the sealing strips and for a better appearance.

The upper construction according to the invention in which a breathable-waterproof laminated material is positioned outside the upper is totally contrary to preconceived ideas about having the waterproof envelope in the foot area and brings numerous advantages in terms of aesthetics, lightness, and efficiency.

Waterproofing the outside of the shoe is indeed much more efficient.

In order to increase waterproofness, one can also provide for:

-   -   applying waterproof TPU glue over all the base seams 3 a of the         upper (upper/sole assembly);     -   applying waterproof TPU glue inside the seams 17, which are         waterproofed by the strip 18 on the upper.

In addition, the aspect of comfort is completely dissociated from the aspect of waterproofness, and comfort is increased. Finally, the construction makes it possible to lighten the structure, and especially to eliminate the additional waterproofing liner, and to facilitate the manufacture insofar as the seams to waterproof are considerably reduced due to the use of elastic materials.

Finally, the construction is waterproof up to the top of the shoe, contrary to the presently known types of constructions.

In the illustrated embodiment shown in FIG. 1 a, and for which similar or identical elements are designated by the same reference numerals, the tongue 15 extends forwardly to the area of the toe cap 12 and is connected on both sides to the vamp 13 by means of two longitudinal seams 17 a, which are waterproofed from the outside by a strip 18.

In this embodiment, the seams 17 a can be of the same type as the seams 17 shown in FIG. 2.

In this case, the tongue 15 has a pattern-cutting adapted to making gussets in the lacing zone 15.

FIG. 4 shows another embodiment in which similar or identical elements are designated by the same reference numerals.

In this case, the only difference with the embodiment of FIGS. 1 to 3 is that the vamp 13 stops in the area of its junction (seam 17) with the reinforcement 16.

In other words, the vamp 13 does not extend down to the insole 3.

The advantage of this construction is that the shoe is made lighter. Furthermore, it can be more comfortable since it does not have any excess thickness.

FIG. 6 shows another embodiment of the assembly seams 27 between the vamp 13 and the reinforcement 16. In this case, the seam 27 is a zigzag seam. Such a seam is advantageous in case an elastic material is used and it also makes it possible to connect the fabrics/inlays 13/16 arranged end-to-end, resulting in a quasi-to-total lack of excess thickness, and therefore in increased comfort.

The present invention is not limited to the particular embodiments hereinabove described by way of non-limiting examples, but encompasses all the similar or equivalent embodiments. 

1. An article of footwear comprising: an outer sole; an outer upper mounted upon the outer sole, the upper comprising: a plurality pieces assembled by at least one stitched assembly seam, said at least one stitched assembly seam including a visible stitched assembly seam; the plurality of pieces comprising breathable-waterproof material; at least the visible assembly seam of the outer upper is covered by a waterproofing sealing strip arranged outside the outer upper.
 2. An article of footwear according to claim 1, wherein: the plurality of pieces of the upper comprises a three-layered laminated material comprising a breathable-waterproof membrane sandwiched between an inner lining fabric and an outer envelope fabric.
 3. An article of footwear according to claim 1, wherein: the plurality of pieces of the upper comprises a slightly extensible material.
 4. An article of footwear according to claim 1, wherein: the waterproofing sealing strip comprises at least one layer of thermofusible adhesive and at least one layer of textile material.
 5. An article of footwear according to claim 1, wherein: the waterproofing sealing strip is extensible.
 6. An article of footwear according to claim 4, wherein: each of the plurality of pieces of the outer upper comprises a textile material having interstices between fibers of the textile material; thermofusible adhesive of the layer of thermofusible adhesive of the waterproofing sealing strip is infused, at least partially, in the interstices between the fibers of the textile material of the outer upper.
 7. An article of footwear shoe according to claim 1, wherein: the outer upper is closed.
 8. An article of footwear shoe according to claim 1, wherein: said plurality of pieces of the outer upper includes a vamp; a longitudinal opening extends adjacent said vamp; and a tongue is positioned within said opening, said tongue being secured to an inner side of said vamp. 